The invention relates to an electronic component and a panel and to a method for producing the same.
Electronic components that have a semiconductor chip and a wiring board arranged on the upper side of the semiconductor chip already form with these components the package of the electronic component. All that is necessary for this purpose is to apply the wiring board to the semiconductor chip with the aid of a double-sided adhesive film. The wiring board carries the external contacts and a patterned metal coating of wiring leads, which lead from the macroscopic output contacts to the microscopically small contact areas of the upper side of the semiconductor chip in a bonding channel of the wiring board. In this connection, microscopically small is understood as meaning a dimension which lies in the micrometer range, and can consequently only be measured with the aid of an optical microscope, whereas the macroscopic external contacts are understood as meaning dimensions which can be perceived with the naked eye and can be measured with simple instruments.
To protect the sensitive semiconductor chip, the upper side of the wiring board, which is connected to the semiconductor chip, may additionally carry a plastic package molding compound. This plastic package molding compound may either protect the edges of the semiconductor chip or completely surround the semiconductor chip, as known from the patent U.S. Pat. No. 6,048,755 for BGA packages (ball grid array packages). For applying such protective plastic package molding compounds to the upper side of the wiring board and for encapsulating the semiconductor chip, either high-pressure injection-molding processes may be used, operating at working pressures of over 100 bar in order to avoid inclusions of air bubbles in the plastic package molding compound, or vacuum printing installations may be used, to ensure back-side protection of the semiconductor chips without air bubbles. Since, in vacuum printing installations, the application or printing of the back sides of the wiring board and the filling of the intermediate spaces between the semiconductor chips is performed under a vacuum, with these installations there is no risk of the inclusion of air bubbles since there is no air in the vacuum.
Both methods of protecting the back sides of the semiconductor chips, that is methods which operate under a vacuum or at high pressure, are costly, but result in the semiconductor chip being encapsulated by a single costly method step. In addition, both methods take up relatively large intermediate spaces between a number of semiconductor chips to be packed simultaneously in plastic molding compound, in order to ensure that the plastic package molding compound is reliably introduced around the semiconductor chips without air bubbles. Attempts to provide low-cost methods which permit the plastic package molding compound to be printed onto the back sides and the edge sides of the semiconductor chips in normal air fail because of the inclusions of air bubbles, in particular if the intermediate spaces between a number of semiconductor chips to be packed in plastic package molding compound become ever closer because of increasing density per unit area being worked.